This callback does not mean that the transaction will actually be committed.
A rollback decision can still occur after this method has been called. This callback
is rather meant to perform work that's only relevant if a commit still has a chance
to happen, such as flushing SQL statements to the database.

Note that exceptions will get propagated to the commit caller and cause a
rollback of the transaction.

afterCommit

Invoked after transaction commit. Can perform further operations right
after the main transaction has successfully committed.

Can e.g. commit further operations that are supposed to follow on a successful
commit of the main transaction, like confirmation messages or emails.

NOTE: The transaction will have been committed already, but the
transactional resources might still be active and accessible. As a consequence,
any data access code triggered at this point will still "participate" in the
original transaction, allowing to perform some cleanup (with no commit following
anymore!), unless it explicitly declares that it needs to run in a separate
transaction. Hence: Use PROPAGATION_REQUIRES_NEW for any
transactional operation that is called from here.

NOTE: The transaction will have been committed or rolled back already,
but the transactional resources might still be active and accessible. As a
consequence, any data access code triggered at this point will still "participate"
in the original transaction, allowing to perform some cleanup (with no commit
following anymore!), unless it explicitly declares that it needs to run in a
separate transaction. Hence: Use PROPAGATION_REQUIRES_NEW
for any transactional operation that is called from here.